A couple foundation related questions

Not sure if I should post these individually, but will ask together first. I purchased a home approx 100 years old which has over the course of its history undergone several renovations, expansions and recoveries. It's on a mostly-accessible crawl space, has been significantly shored up after some major termite damage (in Georgia - fairly common!) and shows evidence of being waterproofed once or twice. Here are my questions:
* There is a French drain that was installed on one side of the house approx 50 feet in length. I don't know how old it is, but it doesn't seem to work well in heavy rains, as some water runs into basement on rare occasion. Is there a way to repair/rejuvenate this or do I need to totally redo from scratch?
* Related, I want to better direct downspouts either into a drainage system or into the French drain. Is it better to make a separate piped run or use the same French drain? I only have about 7 feet to work with to the property line (intown lot) and there is a gas line and water line at forward corner to manuever around.
* Several major support beams in crawl space are on Sonotubes and screw jacks. Other major supports are on round steel beam pillars and multiple minor supports of wood on concrete or brick footers. It looks like a professional job, but there is some floor tilt on 1st floor. Sonotube forms are still on concrete. I have no idea if these were poured on footers or if rebarb was used. Any easy way to tell this? Is it OK to remove the cardboard forms (if nothing else to remove organic material food source for termites?)
* Two of these supports are under one of the worse areas of tilt on first floor. I found one of them loose (basically not supporting a load and causing a dip). Another one seems to be too high. What is best way of balancing between the two?

A couple foundation related questions

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A couple foundation related questions

Not totally my thing, CWIT, but here goes.

If you're already having problems with your perimeter drain (I assume that is what you refer to as a French drain?), adding more water to it doesn't seem wise, and may not be to code, it isn't allowed here.

It's fine to remove the cardboard, it should have been done at the time of building for exactly the reason that you want to do it now. No easy way ot tell whethter you have rebar in the conc. (to my knowledge), To tell if they are on footings, dig down and look.

If you raise the jack on the low one will this bring the high one down? That is: are they see-sawing over another support, or are they on the same side? Either way, you can raise the low one to where it is helping support, but something is apparently moving under there, and you might want to get someone to look at it. If you do try to level the building using these jacks, take it easy, the building took a long time to get where it is now, don't try to move it back all at once. Give it a bit of a tweak, and then don't touch it for a few days, let it get used to the new stress and 'work in'.

I wind up doing a little of this type of thing from time to time, but there are people who do nothing else who will have, perhaps, more to say. Good luck, let us know what happens.

A couple foundation related questions

Quote:

Originally Posted by cwit

Here are my questions:
* Is there a way to repair/rejuvenate [the old french drain] or do I need to totally redo from scratch?
* I want to better direct downspouts either into a drainage system or into the French drain. Is it better to make a separate piped run or use the same French drain?
* Sonotube forms are still on concrete. Is it OK to remove the cardboard forms (if nothing else to remove organic material food source for termites?)

French drains typically 'choke up' because fine soils fill the voids in the aggregate that makes up the drain thereby eliminating its storage capacity. There is no way to 'unchoke' them.

French drains don't typically have an outlet; their effectiveness is a function of the volume of the void in the aggregate and the 'perc' properties of the soil that surrounds the aggregate. If you want downspout runoff to leave your property, or otherwise be drained to 'daylight', then you'll need to pipe it accordingly. Use solid (not perforated) pipe to do so.

Removal of the sonotube presents no detriment to the structural properties of the concrete-leaving it in place no benefit.